Kohler ECV940 Service Manual page 37

throttle body assembly. If no results are found while
performing this test, a small load or gentle back and forth
motion can be applied to connectors or wires just outside
connectors to detect a faulty connection.
If only a volt meter is available
Measure voltage supply to sensor from ECU. This
voltage should be 5.00 +/- 0.20 volts. This can be
measured by gently probing terminals 2 & 3 on harness
side with TPS connector removed from TPS and key
ON. This will generate a P0122 fault that can be cleared
with an ECU reset. If voltage is low, battery, harness and
ECU should be investigated. If supply voltage is good,
plug sensor back into harness. Probe sensor signal
wire with volt meter, terminal 6 at TPS or pin Black 12 at
ECU. This signal should be 0.6-1.2 volts at idle. Since
there is no longer any wear elements inside sensor, most
likely faults will be in electrical connections between
sensor and wire harness and wire harness to ECU.
Engine Temperature Sensor
A sealed, non-serviceable assembly. A faulty sensor
must be replaced. If a blink code indicates a problem
with temperature sensor, it can be tested as follows:
1. Remove temperature sensor from crankcase next to
breather cover and cap or block sensor hole.
2. Wipe sensor clean and allow it to reach room
temperature (25°C, 77°F).
3. Unplug Black connector from ECU.
4. With sensor still connected, check temperature
sensor circuit resistance between Black pin 10 and
14 terminals. Value should be 9000-11000 Ω.
5. Unplug sensor from wire harness and check sensor
resistance separately across two pins. Resistance
value should again be 9000-11000 Ω.
a. If resistance is out of specifi cations, replace
temperature sensor.
b. If it is within specifi cations, proceed to Step 6.
6. Check circuits (input, ground), from wire harness
connector to sensor plug for continuity, damage, etc.
Connect one ohmmeter lead to Black pin 14 in wire
harness connector (as in step 4). Connect other lead
to terminal #1 in sensor plug. Continuity should be
indicated. Repeat test between Black pin 10 and
terminal #2 in sensor plug.
Temperature/Manifold Absolute Pressure (TMAP)
Sensor
A sealed non-serviceable integrated sensor that checks
both intake air temperature and manifold absolute
pressure. Complete replacement is required if it is faulty.
Sensor and wiring harness can be checked as follows.
If a blink code indicates a problem with Intake Air
Temperature (TMAP) Sensor Circuit (P0112 or P0113), it
can be tested as follows:
1. Remove TMAP sensor from intake manifold.
2. Allow it to reach room temperature (20°C, 68°F).
3. Unplug Black connector from ECU.
4. With sensor still connected, check temperature
sensor circuit resistance between Black pin 10 and 8
pin terminals. Value should be 1850-2450 Ω.
62 690 05 Rev. H
EFI SYSTEM-ELECTRONIC THROTTLE BODY (ETB)
5. Unplug sensor from wire harness and check sensor
6. Check circuits (input, ground), from main harness
7. Reinstall sensor.
If a blink code indicates a problem with Manifold
Absolute Pressure (TMAP) Sensor Circuit (P0107 or
P0108), it can be tested as follows:
1. Make sure all connections are making proper
2. Check continuity in wire harness. Ohms between Pin
3. Check to make sure intake manifold is not loose and
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resistance separately across pin. Resistance value
should again be 1850-2450 Ω.
a. If resistance is out of specifi cations, check local
temperature. Sensor resistance will go down as
temperature is higher. Replace TMAP sensor if
determined to be faulty.
b. If it is within specifi cations, proceed to Step 6.
connector to sensor plug for continuity, damage, etc.
Connect one ohmmeter lead to Black pin 8 in main
harness connector (as in step 4). Connect other lead
to terminal #3 in sensor plug. Continuity should be
indicated. Repeat test between Black pin 10 and
terminal #4 in sensor plug.
contact and are free of dirt and debris. Slide locking
tab out and pull off TMAP connector. Turn key switch
to ON and check with a volt meter by contacting red
lead to pin 1 and black lead to pin 2. There should
be 5 volts present, indicating ECU and wiring
harness are functioning.
3 at sensor connector and Black pin 11 connector at
ECU should be near zero ohms. If no continuity is
measured or very high resistance, replace wire
harness.
TMAP sensor is not loose. Loose parts would allow
a vacuum leak, making TMAP sensor report
misleading information to ECU.
a. Tighten all hardware and perform an ECU Reset
Procedure to see if MIL will display a fault with
sensor again. If MIL fi nds a fault with TMAP
sensor, replace it.
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